


Double, Double, Toil and Trouble

by naucturnal



Category: Shadowhunters (TV)
Genre: Angst and Humor, Body Doubles, M/M, POV Multiple, Parabatai, cuz that's my jam, p.s. I'm admittedly horrible at updating, set vaguely mid-series
Language: English
Status: In-Progress
Published: 2020-07-27
Updated: 2021-02-06
Packaged: 2021-03-05 21:35:22
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 3
Words: 2,588
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25552162
Author URL: https://archiveofourown.org/users/naucturnal/pseuds/naucturnal
Summary: Clary's gaze flits between the two identical Shadowhunters. Leather outfits and gear, identical. Rune placement, identical. Ridiculous height, identical. Scowling expressions, most definitely identical.Well, damn. Clary has seen a lot since she learned she was a Shadowhunter. She still has wonder for the abilities of the Shadow World, but rarely disbelief. But magic or not, she didn't think anyone would quite be able to imitate Alec's particular brand of disapproval. The sight in front of her proves her wrong."It's me," the voices growl in unison.Clary's grip on her dual daggers tightens.
Relationships: Alec Lightwood & Jace Wayland, Magnus Bane/Alec Lightwood
Comments: 6
Kudos: 62





	1. Chapter 1

Clary's gaze flits between the two identical Shadowhunters. Leather outfits and gear, identical. Rune placement, identical. Ridiculous height, identical. Scowling expressions, most definitely identical.

Well, damn. Clary has seen a lot since she learned she was a Shadowhunter. She still has wonder for the abilities of the Shadow World, but rarely disbelief. But magic or not, she didn't think anyone would quite be able to imitate Alec's particular brand of disapproval. The sight in front of her proves her wrong.

"It's me," the voices growl in unison.

Clary's grip on her dual daggers tightens.

* * *

It didn't take long from when Clary first came across Alec and...Alec for Magnus, Jace, Izzy, and Simon to rush to the scene. They're currently in an empty room of the Institute, with the situation on a need to know basis. The doubles had for the most part been compliant in being led to a more private space. Whatever protests they had died down the minute Clary warned she'd scream the entire Institute into high alert. 

Now they're all armed and have formed a half-circle in standoff against the two Alecs. Despite this, they both seemed more annoyed than threatened. "Look," they begin, one reaching an arm out and the other taking a step forward.

In a flash, Simon zips behind them both, holding each by the collar of their leather jacket. One bristles and the other lets out a miffed, "Simon, let go of me."

"Oh my G—agh!" Simon's exultation is is cut short by his vampiric difficulty to say _God_ but Clary would recognize the signs of excited babble to come anywhere. "He called me Simon! He got my name right! Real Alec would never do that. I mean, at this point he's just insisting on getting it wrong. I'm pretty sure? Is it possible he doesn't actually know? Hey, Alec, my name is Simon. Si-mon. I'm the Vampire? Formerly Mundane? Clary's bestie? Remember that time we went to Clary's apartment together to look for the Cup and—"

"I know who you are," one of them says. The other grits out, "Shut. Up."

"Jace," Magnus intones, and for once his voice doesn't belie the centuries of power behind it. "Use your parabatai rune to feel Alec." He doesn't say the _real_ Alec, doesn't acknowledge the imitation.

"I can't!" Jace confesses, and Clary has seldom heard him sound so helpless. "It-it's like the bond is echoing. I'm...drawn to both of them."

Well, that can't be right. Clary has seen the parabatai bond in action, seen it stretch across life and death. Jace has talked about the bond in all forms, feeling weak, blocked, or transmitting strong emotions. Clary remembers when she and Jace had had some rare downtime away from everyone else. Izzy was in the lab, Simon was at the DuMort, and Alec was away from the Institute for the night. Clary and Jace were bantering as she sketched him when his eyes suddenly widened and he grumbled to himself, "For Angel's sake, Alec!" "Everything OK?" Clary had asked, as Jace looked down at his parabatai rune. When his gaze came back up to meet hers, he was blushing. "Yep...just dandy." So maybe Clary can't even begin to understand the mysteries of the parabatai rune, but she's never seen Jace react to it with uncertainty, and that's more worrying than the doubles standing in front of them. 

By the grim set of his mouth, Magnus seems to share her concern. "Then I'll have to run a magic scan." Magnus's hands glow and he closes his eyes in concentration. Both Alecs watch on in interest. After a moment, Magnus blinks to reveal his natural cat eyes. He looks the Alecs up and down, as if seeing them for the first time. The group all wait with bated breath until Izzy can't stand it anymore and blurts, "Magnus! What do you see?"

Magnus sighs as his eyes glamour back to brown. "It's not possible, but they have the same energy signature."

"What does that mean?" Jace asks hotly. Clary's not quite sure what an energy signature is, but if it's anything what it sounds like...She turns to look at Izzy, who, as expected, has on a thoughtful expression. "That's not possible, scientifically nor magically. But it would mean they're essentially the same version of the same person."

"By same version, you mean not from an alternate dimension," Clary states. A few heads turn to her in surprise, but Clary is more than familiar with alternate dimensions.

The Alecs have been patient this whole time, and now one speaks up, "I told you it's me." The other simply raises his eyebrows.

"Well this is certainly perplexing," Magnus says. His voice is nonchalant as he waves a hand indicating the two Alecs, but there's tightness around his eyes. "What appeared to be an impeccable case of shapeshifting might actually be Alexander...split in two."

**Notes for the Chapter:**

> Dun dun DUNNNN!! ;)


	2. Chapter 2

It reminds him of a horror movie he watched with Magnus. Not one of Magnus's preferred genres, but he had insisted on introducing Alec to the full range of film to get a feel for his favourites (Westerns, it turns out). 

The day started out as usual with Alec waking a minute before his alarm clock, remnants of a dream slipping out of reach. He reaches out to turn off the alarm before it could start blaring and gets up, heading to the small ensuite in his room at the Institute. His morning routine is swift. After splashing cold water on his face in front of the mirror, he pats his face dry with a particularly fluffy towel, courtesy of Magnus. When he looks back at his reflection, there's nothing there. 

Alec feels the hairs on the back of his neck stand up. He allows for a moment of terror before turning around. What he sees is...himself. He's wearing the same black t-shirt and grey sweatpants. There's a tendril of wet hair he missed when drying. There's a towel pulled tightly in his grip.

Of course, Alec's first instinct is to attack.

So is his double's. 

They end up in a stalemate, each with a towel wrapped taut around the other's neck—and their own. For a moment, Alec considers just going ahead and choking the life out of this abomination and damn if he goes down with it. From the glint in his double's eye, it looks like he's thinking it too. 

Alec loosens his grip on the towel and feels the tightness around his own neck ease. He takes in their positions in the tiny room and notices by pure luck he has the advantage. Alec lets go of his towel entirely, surprising the double and using the unexpected moment to push him against the bathroom door, where the spindly door handle will dig in between his vertebrae. From the hiss the double lets out, he knows his plan was a success.

While the double's down, Alec rips the remaining towel from out of his grasp and goes in for the kill, no questions asked. The Clave's going to be pissed he didn't get more information out of...whatever this was, but it's too dangerous. Against an opponent with an identical skill set, Alec can't afford to lose the upper hand. Things have to end here, whether by victory or draw. If the double gets out, he'll wreak havoc on the Institute. Angel knows it's happened before. They'll have to take him down, but Jace will be impaired by the severed parabatai bond and Magnus—

"They'll kill you." 

Alec's thoughts are interrupted by the double's words, the first either of them has spoken. _Is that what my voice sounds like?_ Alec muses as he keeps pulling the towel tight. 

"They'll figure out it's not me and kill you," the double grits out while he can, futile hands scrabbling at his throat. "Jace, Izzy, Mag—" 

The parallel line of thought spooks Alec enough that he lets the towel slacken slightly. "What are you saying?" 

The double looks resigned but haughty, even with a red face. "Whatever your plan is, it's not going to work. You may look the part but it doesn't matter. My team—my _family_ won't be fooled. And when they find out you're an imposter, you're going to die. Painfully." 

  
Alec is bewildered. " _I'm_ the imposter?"

"Don't know if you've done your research but I'm a parabatai," the double goes on. He drops a hand down from his throat to tug up the side of his shirt, revealing a parabatai rune. "The moment I'm dead, my parabatai will know, and it won't matter how good of a copy you are. Kind of a glaring error there, huh?"

With one hand still at the double's throat, Alec reaches the other out towards the rune under the double's hateful gaze. Alec's fingers waver hesitantly over the rune and that's all the distraction the double needs. He bucks Alec's hand off his throat and body slams Alec. As they collide, Alec feels a pulse through the parabatai rune and leaps back. The double looks just as startled. "Did you just..."

In reply, Alec lifts up his own shirt, revealing the parabatai rune. "Looks like I'm not an imposter after all," he says. "And neither are you."

* * *

"So that's how you two came to trust each other. You could feel the parabatai bond?" Izzy asks. They're all still standing tensely in the otherwise empty room. Simon, who had been standing behind the Alecs to hold them in place, shuffles awkwardly back towards the rest of the group.

"Yeah," one Alec replies. He looks towards the other. "But it's not like how it is between me and Jace." 

"It more like a split," the other Alec supplies.

"Jace? Does that make sense?" Clary asks. 

Jace presses a hand on his parabatai bond, closing his eyes in concentration. "I guess so. Right now the bond has two paths that come together into one at my end. Like a Y." 

"That settles it," Magnus says. "There's no magic that can alter the parabatai bond like that. They're both Alec." 

"So do you share the same thoughts then? Like a Vulcan mind meld situation?" Simon blurts. He receives two identical glares in response. "I don't know what that is," one of them bothers to say. 

"Can you hear what the other is thinking? Or communicate with them telepathically?" Magnus explains.

"No," one Alec says as the other shakes his head. "We just happen to think the same." 

"Because so far you've both received identical external stimuli. We need to separate you to test this out," Izzy says briskly. 

"Fine by me," one Alec says and the other twists his mouth in an expression that says the same. 

"So...how do we decide who goes with who?" Clary asks. She hates how lost Jace looks, eyes darting between the doubles.

As if on cue, the Alecs step apart at the same time, moving toward either side of the group. 

"That'll work," Magnus says, looking around the group. "Alexander, you'll come with myself and Simon. And...Alexander, you can stay with Jace, Clary, and Isabelle at the Institute. We'll spend some time apart then regroup to learn more about this...situation," he says delicately.

The Alec next to Magnus smirks. "I have some Clave paperwork to take care of today."

"Yes, _I_ do," the other Alec rolls his eyes. 

"Don't worry, Alec," Jace says, clapping a hand on the one next to him. He seems a bit more at ease with his parabatai in reach. "We gotta test you out sparring, too. There'll be plenty of paperwork left over." 

**Notes for the Chapter:**

> On the next episode...double the Alecs, double the pleas—nah, it's just double the paperwork.


	3. Chapter 3

"Just a bit more..." Izzy says, squinting at a test tube. She bends back down towards Alec's torso, a scalpel in hand. 

"Got it!" she exclaims triumphantly, loud enough to cover up the small squeak Alec let out at the procedure. Jace only heard it because he's pretty sure he let one out too. Izzy had scraped along the parabatai rune to collect a sample of Alec's angelic energy.

Izzy's taking samples from the Alecs for further investigation in the lab. Even if by all accounts they are the same person, they'll be having different experiences now. These first samples will be the controls, which she'll compare to samples taken later to see if and how being apart has affected the two. Or something like that? Admittedly, Jace tuned out partly through her explanation. He's waiting for everything to finish up so that he and Alec ( _this_ Alec) can get to sparring.

"I got everything I need from both Alecs now, so I'll go straight to the lab. Clary, can you help me carry this set of samples?" Izzy asks, handing Clary a set of test tubes. 

"Sure," Clary says. "Which Alec do these belong to?" 

"Those are from the Alec going with Magnus and these are from the Alec staying with Jace," Izzy gestures to the tubes in her hand. "I'll label them 'M-Alec' and 'J-Alec' so they don't get mixed up." 

"Enjoy your session!" Izzy links her arm with Clary's and they head towards the laboratory.

Magnus, Simon, and Alec had already portalled away, so that leaves Jace and Alec on their own for the first time all day. Without the distractions, Jace tries to sense if anything's off. He must be staring too hard because Alec raises an eyebrow like he knows just what Jace is thinking. Jace gives him a rueful grin and leads the way into the training room.

They prepare for hand-to-hand sparring and activate each other's runes as usual. Strength, Speed, and Stamina. After that, it's steles away and into starting positions. 

* * *

"So you doing good?" Jace asks, narrowly dodging an uppercut. Sparring doesn't leave much room for conversation, which is how they prefer it. 

"Yeah," Alec lets out, pivoting. "Better than when I thought he was a threat." 

For Alec to trust someone—even _himself—_ is no small feat. And it must be true because their bond isn't particularly thrumming with distress, nor is it closed off. 

"That's good," Jace says, whipping his elbow forward. _Ah, almost!_ He grins and directs his attention back to the fight.

They continue to spar for a while and are about to wrap up. Jace reflects back on the time and honestly, it doesn't feel any different than sparring with Alec usually does. Maybe there is another one of him out there, but the one here is Alec through and through. 

Jace's runes are running low but he's still high on the thrill of the fight. Bouncing on his heels, he feints left then goes in with a jab to the right. Jace's fist cuts through thin air.

Alec dodged the blow quicker than Jace thought possible. Damn, Jace must have projected his excitement through the bond and telegraphed his move! He's admittedly careless about closing the bond while fighting, because it's not like he'd actually do it in the field. 

Jace shakes his head with a rueful grin. "Nice one, you got me there, Alec!" He reaches out a hand to Alec who dropped to the ground in a squat. He could have kicked Jace's legs out from under him by now. He's either being charitable, or knows that not even bothering to go through with it will just rub in the victory more. 

Alec doesn't take his hand, doesn't even look up at Jace. 

"Alec?"

Alec lists to the side and collapses in a boneless heap.

"Alec!!"


End file.
